Major space mystery solved using data from student satellite

Dozens of CU Boulder students designed and built the CSSWE CubeSat satellite, which was used to study energetic particles in the Van Allen radiation belts. Credit: University of Colorado

A 60-year-old mystery regarding the source of some energetic and potentially damaging particles in Earth's radiation belts is now solved using data from a shoebox-sized satellite built and operated by University of Colorado Boulder students.

The results from the new study indicate energetic electrons in Earth's inner radiation belt - primarily near its inner edge - are created by cosmic rays born from explosions of supernovas, said the study's lead author, Professor Xinlin Li of CU Boulder's Laboratory for Atmospheric and Space Physics (LASP). Earth's radiation belts, known as the Van Allen belts, are layers of energetic particles held in place by Earth's magnetic field.

The team showed that during a process called "cosmic ray albedo neutron decay" (CRAND), cosmic rays entering Earth's atmosphere collide with neutral atoms, creating a "splash" which produces charged particles, including electrons, that become trapped by Earth's magnetic fields. The findings have implications for understanding and better forecasting the arrival of energetic electrons in near-Earth space, which can damage satellites and threaten the health of space-walking astronauts, said Li.

"We are reporting the first direct detection of these energetic electrons near the inner edge of Earth's radiation belt," said Li, also a professor in CU-Boulder's aerospace engineering sciences department. "We have finally solved a six-decade-long mystery." A paper on the subject was published in the Dec. 13 issue of Nature. The study was funded primarily by the National Science Foundation.

Researchers test the CubeSat, which is communicating with a ground station about four miles away. Credit: University of Colorado Boulder

Soon after the discovery of the Van Allen radiation belts in 1958, both American and Russian scientists concluded that CRAND was likely the source of high-energy protons trapped in Earth's magnetic field. But over the intervening decades, no one successfully detected the corresponding electrons that should be produced during the neutron decay.

The CubeSat mission, called the Colorado Student Space Weather Experiment (CSSWE), houses a small, energetic particle telescope to measure the flux of solar energetic protons and Earth's radiation belt electrons. Launched in 2012, CSSWE has involved more than 65 CU Boulder students and was operated for more than two years from a ground station they built on the roof of a LASP building on campus.

The CubeSat just before it was brought into the launch facility. Credit: University of Colorado Boulder

The instrument on CSSWE, called the Relativistic, Electron and Proton Telescope integrated little experiment (REPTile) is a smaller version of REPT, twin instruments developed by a CU Boulder team led by LASP director and Nature paper co-author Daniel Baker that were launched on NASA's 2012 Van Allen Probes mission.

"This is really a beautiful result and a big insight derived from a remarkably inexpensive student satellite, illustrating that good things can come in small packages," said Baker. "It's a major discovery that has been there all along, a demonstration that Yogi Berra was correct when he remarked 'You can observe a lot just by looking.'"

Assembling the only science payload onboard; it sent back high-quality data, researchers report. Credit: University of Colorado Boulder
"These results reveal, for the first time, how energetic charged particles in the near-Earth space environment are created," said Irfan Azeem, a program director in the NSF's Division of Atmospheric and Geospace Sciences.

"The findings will significantly improve our understanding of the Earth-space environment," Azeem said. "It's exciting to see NSF-funded CubeSats built by undergraduate and graduate students at the center of a significant scientific discovery."

Related Stories

Scientists have long known that solar-energized particles trapped around the planet are sometimes scattered into Earth's upper atmosphere where they can contribute to beautiful auroral displays. Yet for decades, no one has ...

Earth's radiation belts, two doughnut-shaped regions of charged particles encircling our planet, were discovered more than 50 years ago, but their behavior is still not completely understood. Now, new observations from NASA's ...

The radiation belts of Earth and Saturn differ more strongly than previously assumed. In these belts, very energetic particles, such as electrons and protons, move around the planet at high velocities - captured by its magnetic ...

(PhysOrg.com) -- The University of Colorado at Boulder has been awarded $840,000 from the National Science Foundation for students to build a tiny spacecraft to observe energetic particles in space that should give scientists ...

Most satellites, not designed to withstand high levels of particle radiation, wouldn't last a day in the Van Allen Radiation belts. Trapped by Earth's magnetic field into two giant belts around the planet, high-energy particles ...

(Phys.org) —Since the discovery of the Van Allen radiation belts in in the Earth's upper atmosphere in 1958, space scientists have believed that these belts consisted of two doughnut-shaped rings of highly charged particles—an ...

Recommended for you

Researchers from RIKEN and JAXA have used observations from the ALMA radio observatory located in northern Chile and managed by an international consortium including the National Astronomical Observatory of Japan (NAOJ) to ...

Using the Visible and Infrared Survey Telescope for Astronomy (VISTA), astronomers have detected a new bright quasar at a redshift of about 6.8. The newly identified quasar, designated VHS J0411-0907, is the brightest object ...

Fifty years ago on Christmas Eve, a tumultuous year of assassinations, riots and war drew to a close in heroic and hopeful fashion with the three Apollo 8 astronauts reading from the Book of Genesis on live TV as they orbited ...

A relic cloud of gas, orphaned after the Big Bang, has been discovered in the distant universe by astronomers using the world's most powerful optical telescope, the W. M. Keck Observatory on Maunakea, Hawaii.

In their search for life in solar systems near and far, researchers have often accepted the presence of oxygen in a planet's atmosphere as the surest sign that life may be present there. A new Johns Hopkins study, however, ...

0 comments

Please sign in to add a comment.
Registration is free, and takes less than a minute.
Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.